A variety of devices for spacing studs, joists, rafters, and similar frame members during construction have been reported in the patent literature. Many of these spacing tools enable the user to position a frame member with respect to a previously positioned frame member prior to attachment to the frame. In particular, U.S. Pat. No. 5,490,334, assigned to the assignee of the present application and incorporated herein by reference, discloses a spacing tool which accomplishes the above as well as assists in speeding construction. Using the spacing tool of the '334 patent, a newly positioned and attached frame member serves as a reference to position a subsequent frame member, and the process is repeated until the frame assembly is complete. The spacing tool of the '334 patent has a cradle and shoulder for engaging the frame members, set apart at a fixed distance corresponding to the desired spacing interval.
Classically, construction frame members have consisted of lumber with a nominal width of two inches and have been separated by spacing intervals of sixteen inches from center to center. For this reason, spacing tools have usually been designed to accommodate such fixed frame member width and spacing interval dimensions. More recently, construction has used fabricated lumber, such as wooden I beams, prefabricated trusses, or metal studs, which are produced in various widths and utilize various center-to-center spacing intervals. Thus there is a need for a spacing tool which can accommodate a variety of frame member widths, such as 11/2", 13/4", 25/16", and 31/2". Additionally, the spacing interval may be varied, with spacing intervals of 12 inches, 13.7 inches, 16 inches, 19.2 inches, and 24 inches being frequently used. Thus, there is also a need for a spacing tool where the spacing interval can be varied.
The need to adjust the spacing interval between the frame members and allow for adjustment to accept frame members of various widths has in part been met by the '334 patent which discloses an adjustable spacing tool having an elongated body, a cradle, and a shoulder. The cradle is composed of two brackets, the separation of which is adjustable by sliding the brackets longitudinally along a channel in the elongated body with which they are slidably and lockably engaged to accommodate various widths of frame members. The shoulder is formed by a third bracket which is longitudinally adjustable by sliding along a second channel in the elongated body with which it is slidably and lockably engaged. The employment of first and second channels to vary the separation between the cradle and the shoulder enables the spacing interval between the frame members to be varied to only a limited degree. Furthermore, the teaching of the '334 patent results in a tool of reduced strength and rigidity and increases the complexity of fabrication of the spacing tool by requiring channels which must either be machined or, when molded, the mold for which requires retractable inserts which greatly increase the mold cost.
Thus, there is a need for a rigid, relatively high strength spacing tool which can be simply manufactured and which will accommodate a wide range of variation in both the frame member width and the spacing interval.